National Security Advisor MK Narayanan says India abhors the political vacuum in Pakistan created by the tussle between President Pervez Musharraf and the PPP-led ruling coalition.

India abhors the "political vacuum" in Pakistan created by the tussle between President Pervez Musharraf and the Pakistan People's Party-led ruling coalition, says National Security Advisor MK Narayanan.

Narayanan said in an interview published on Tuesday that New Delhi was seriously concerned that this vacuum could allow radical extremist outfits in Pakistan more space to step up their activities not only in Afghanistan but also in India.

Pakistan's ruling coalition has vowed to impeach Musharraf unless he quits the presidency. If he is impeached, he could be forced to leave Pakistan.

Narayanan said the worry in India was not if Musharraf would be impeached or not but the inability to identify "who controls all the levers" in Pakistan.

"Whether he is impeached or not is not important from the Indian point of view. It is for the people of Pakistan to decide," Narayanan said.

"But it leaves a big vacuum and we are deeply concerned about this vacuum because it leaves the radical extremist outfits with freedom to do what they like, not merely on Pak(istan)-Afghan border but clearly our side of the border too."

The suicide bombing at the Indian embassy in Kabul last month that killed two Indian diplomats among others has raised New Delhi's worries about the link between terrorists and a section in the Pakistani establishment.

Narayanan was the first one to publicly blame Pakistan's Inter-Services Intelligence (ISI) for the attack. The US has since echoed the complaint.

Narayanan said that during a meeting on the sidelines of the SAARC summit in Colombo earlier this month Prime Minister Manmohan Singh told his Pakistani counterpart Yousaf Raza Gilani that it could not be "business as usual" between the two countries because what happened in Afghanistan was "fundamentally different" from what had happened before.

"An attack on Indian embassy in a foreign land clearly marked an entirely new stage in the levels of acrimony and violence," Narayanan said.

He told the Straits Times: "Therefore we expect something would be done than mere words. (Manmohan) Singh did not raise his voice but left nobody in that room in any doubt on where he stood."

Narayanan said India had been careful in not blaming the Pakistani political "hierarchy" about the attack but it had information that the ISI was behind the Kabul bombing.

"We would expect that the (political leadership) would take some action against it. Either against rogue elements in it, or an ISI operating without control," the NSA said.

He pointed out that in any democratic country, if an agency operated out of step with whatever the political leadership believed in, the agency head or operational chief suffers.